1. Technical Field of the Invention
This invention relates generally to wireless communications, and more particularly to subscriber based wireless voice and data services.
2. Related Art
Wireless communications are well known in the art. Wireless communications include Wireless Local Area Network (WLAN) communications, Wireless Wide Area Network (WWAN) communications, Wireless Personal Area Network (WPAN) communications, and cellular communications, among other wireless communications. Cellular communication systems are well known to include one or more cellular wireless networks, each of which supports cellular wireless communications with cellular telephones (wireless devices). Cellular wireless networks typically support one or more cellular communication operating standards such as the Global Standards for Mobile communication (GSM) standards, the North American Code Division Multiple Access (CDMA) communication standards, the North American Time Division Multiple Access (TDMA) communication standards, the GSM Packet Radio System (GPRS) standards, the Enhanced Data for GSM Evolution (EDGE) standards, the 1xEV-DO standards, the 1xEV-DV standards, and the Universal Mobile Telecommunications System (UMTS) standards, among others.
With cellular communications, a user of a cellular telephone (wireless device) typically contracts with a particular wireless network service provider, “contracted service provider” for cellular wireless network access and usage under a respective service plan. With one example of such an arrangement, a user of a cellular telephone contracts with an operator of a cellular wireless network within North America, e.g., the United States. With this example, the contracted service provider has a GSM cellular wireless network infrastructure (or is contracted with one) that provides wireless service within at least a portion of the United States and has roaming agreements with differing service providers within the United States, with service providers of differing countries, e.g., Canada, Mexico, and/or with service providers of differing continents, e.g., Europe, Asia, etc. With this structure/schema, the user of the cellular telephone receives cellular service not only from the contracted cellular service provider but from cellular service providers having roaming agreements with the contracted service provider.
When a subscriber contracts for service with his/her contracted service provider, the user is issued a System Interface Module (SIM) card, which is installed within the subscriber's cellular telephone. The contract for service may be on a periodic basis, month-to-month, or for a differing period of time. The SIM card includes information regarding the contracted service provider, information that identifies the subscriber, and information that allows a cellular wireless network to authenticate the SIM card. Prior to providing wireless service to a cellular telephone, a servicing cellular wireless network receives information from the SIM card and authenticates the SIM card/cellular telephone using such information and additional information retrieved from a differing device, e.g., contracted service provider's server computer.
Only if the cellular telephone having the SIM card is operating within the cellular wireless network service coverage area of the contracted service provider or operating within a service coverage area of a cellular wireless network of a service provider that has a roaming agreement with the contracted service provider, will the cellular telephone be able to receive service. It is not uncommon for the coverage areas of a number of cellular wireless networks to overlay one another. Further, it is not uncommon for a cellular telephone to support two or more cellular interface standards. Thus, in many operations, a cellular telephone is not able to access available cellular wireless networks solely due to lack of/limitations in roaming agreements between the contracted service provider and an operator of an available cellular wireless network. The problem with accessing cellular wireless networks of other service providers is acute in geographical areas where many differing cellular wireless networks exist within a relatively small geographic area and/or while the cellular telephone is far from its home location area. In Europe, for example, a particular subscriber may have a very limited area in which he or she may access cellular wireless network service due to lack of roaming agreements between the contracted service provider and other cellular wireless networks.
Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such systems with some aspects of the present invention as set forth in the remainder of the present application with reference to the drawings.